Dataset Information

Predominant leptospiral serogroups circulating among humans, livestock and wildlife in Katavi-Rukwa ecosystem, Tanzania.

ABSTRACT:

Background

Leptospirosis is a worldwide zoonotic disease and a serious, under-reported public health problem, particularly in rural areas of Tanzania. In the Katavi-Rukwa ecosystem, humans, livestock and wildlife live in close proximity, which exposes them to the risk of a number of zoonotic infectious diseases, including leptospirosis.

Methodology/principal findings

A cross-sectional epidemiological study was carried out in the Katavi region, South-west Tanzania, to determine the seroprevalence of Leptospira spp in humans, domestic ruminants and wildlife. Blood samples were collected from humans (n = 267), cattle (n = 1,103), goats (n = 248), buffaloes (n = 38), zebra (n = 2), lions (n = 2), rodents (n = 207) and shrews (n = 11). Decanted sera were tested using the Microscopic Agglutination Test (MAT) for antibodies against six live serogroups belonging to the Leptospira spp, with a cutoff point of ? 1:160. The prevalence of leptospiral antibodies was 29.96% in humans, 30.37% in cattle, 8.47% in goats, 28.95% in buffaloes, 20.29% in rodents and 9.09% in shrews. Additionally, one of the two samples in lions was seropositive. A significant difference in the prevalence P<0.05 was observed between cattle and goats. No significant difference in prevalence was observed with respect to age and sex in humans or any of the sampled animal species. The most prevalent serogroups with antibodies of Leptospira spp were Sejroe, Hebdomadis, Grippotyphosa, Icterohaemorrhagie and Australis, which were detected in humans, cattle, goats and buffaloes; Sejroe and Grippotyphosa, which were detected in a lion; Australis, Icterohaemorrhagie and Grippotyphosa, which were detected in rodents; and Australis, which was detected in shrews. Antibodies to serogroup Ballum were detected only in humans.

Conclusions

The results of this study demonstrate that leptospiral antibodies are widely prevalent in humans, livestock and wildlife from the Katavi-Rukwa ecosystem. The disease poses a serious economic and public health threat in the study area. This epidemiological study provides information on circulating serogroups, which will be essential in designing intervention measures to reduce the risk of disease transmission.

SUBMITTER: Assenga JA

PROVIDER: S-EPMC4373666 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Publications

Predominant leptospiral serogroups circulating among humans, livestock and wildlife in Katavi-Rukwa ecosystem, Tanzania.

Assenga Justine A JA Matemba Lucas E LE Muller Shabani K SK Mhamphi Ginethon G GG Kazwala Rudovick R RR

PLoS neglected tropical diseases 20150325 3

<h4>Background</h4>Leptospirosis is a worldwide zoonotic disease and a serious, under-reported public health problem, particularly in rural areas of Tanzania. In the Katavi-Rukwa ecosystem, humans, livestock and wildlife live in close proximity, which exposes them to the risk of a number of zoonotic infectious diseases, including leptospirosis.<h4>Methodology/principal findings</h4>A cross-sectional epidemiological study was carried out in the Katavi region, South-west Tanzania, to determine the ...[more]

PMID: 25806825

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Project description:Leptospirosis is a neglected zoonotic disease of worldwide public health importance. The disease affects humans, domestic animals and wildlife. However, leptospirosis is challenging in its diagnosis in humans. Culture technique, which is time consuming, is not recommended for clinical diagnosis. For these reasons, serological and molecular techniques remain the test of choice. The major objective of this study was to explore the genetic characteristic of Leptospira species which are prevalent among agro-pastoralists living in Katavi-Rukwa Ecosystem, Tanzania.A cross-sectional epidemiological study was carried out in the Katavi-Region South-west, Tanzania between August, 2013 and November, 2014. A total of 267 participants were randomly recruited for the study. Microscopic agglutination test (MAT) was used to detect antibody against six Leptospira antigens including local serogroups Icterohaemorrhagiae, Ballum, Grippotyphosa, Sejroe and reference serogroups Hebdomadis, and Australis. Samples with MAT titers???1:160 were scored as positive, samples with MAT titers ranging from 1:20 to 1:80 were scored as exposed to Leptospira, and absence of agglutination titers was scored as negative. All MAT positive samples, including the low titre samples were subjected to PCR using the respective 16S rRNA primers for the pathogenic and non-pathogenic species.Out of 267 samples tested, 80 (29.9 %) were positive with MAT. The major circulating leptospiral serogroups were Sejroe (15.7 %,), Icterohaemorrhagiae (8.9 %), Grippotyphosa (4.8 %), Hebdomadis (3.37 %), Australis (1.49 %) and Ballum (1.19 %). By using PCR, 33 (15.7 %) out of 210 samples were pathogenic Leptospira while no saprophytic Leptospira spp. was detected. Partial 16S rRNA gene sequences of Leptospira species which were obtained from this study were submitted to GenBank and acquired accession numbers KP313246 and KP313247. Phylogenetic analysis of the nucleotide sequences revealed that species obtained from Katavi-Rukwa ecosystem clustered in the same group with several published pathogenic Leptospira specifically Leptospira interrogans and Leptospira kirschneri. To the best of the authors' knowledge(,) this is the first study from Tanzania to confirm pathogenic Leptospira in human subjects using genomic typing technique.These findings provide ultimate evidence of pathogenic Leptospira species circulating among agro-pastoralists living in Katavi-Rukwa Ecosystem suggesting that active disease surveillance should be undertaken in order to achieve greater protection of the agro-pastoral communities in Tanzania.

Project description:BACKGROUND:Brucellosis is a zoonotic disease transmitted to humans through contact with infected animals, animal products or consumption of infected dairy products. Brucella infection during pregnancy is of special interest due to association with adverse pregnancy outcomes. This study determined the seroprevalence and factors associated with Brucella infection among pregnant women around the human-wildlife-livestock interface area in Ngorongoro ecosystem, Northern Tanzania. METHODS:A facility-based cross-sectional study was conducted between May and June 2018 at six health facilities that provide antenatal services. Pregnant women receiving antenatal care were invited to participate. A structured questionnaire was used to collect socio-demographic and obstetric characteristics in addition to behavior and practices related to the occurrence of human brucellosis. The presence of serum immunoglobulin against Brucella was determined using Rose Bengal Plate Test (RBPT). The positive samples were further assayed for the presence of IgG and IgM using The enzyme-linkedimmunosorbent assay. Bivariate analysis was conducted to determine the variables associated with Brucella seropositivity. Multivariable logistic regression analysis was performed to examine the factors independently associations with Brucella seropositivity after adjustment for other explanatory variables. RESULTS:A total of 313 participants were enrolled in the study. The overall seroprevalence of Brucella infection was 10.9% (34/313) determined by Rose Bengal plate test. Of 34 positive individuals, 27(79.4%) and 8(23.5%) were positive in the ELISA specific for IgG and IgM Brucella antibodies respectively. Regular contact with manure (AOR 3.16, 95%CI 1.27-7.83) and preference for animal fresh milk (AOR 3.80, 95% CI 1.23-11.69), raw meat (AOR 2.58, 95% CI 1.14-5.81) and raw animal blood (AOR 2.71, 95% CI 1.15-6.35) increased the odds of being Brucella seropositive. Contact with the animal placenta were not associated with Brucella seropositivity after adjustment. CONCLUSION:This study has found that brucellosis is an important public health problem among pregnant women in areas with interactions of humans; livestock and wildlife. The risk of infection increased with the regular contact with manure and preference of raw foodstuffs like animal blood, meat, and milk. We emphasize the need for interventional strategies to reduce the risk of exposure.

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Dataset Information

Predominant leptospiral serogroups circulating among humans, livestock and wildlife in Katavi-Rukwa ecosystem, Tanzania.

Background

Methodology/principal findings

Conclusions

Publications

Predominant leptospiral serogroups circulating among humans, livestock and wildlife in Katavi-Rukwa ecosystem, Tanzania.

Similar Datasets

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